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How NASA's Soil Moisture Satellite Works (Infographic)

Diagrams explain how NASA's SMAP satellite works.
SMAP, or "Soil Moisture Active Passive," will measure groundwater content and frozen/thawed state, all over the world every three days.
(Image: © By Karl Tate, Infographics Artist)

The satellite called SMAP (Soil Moisture Active Passive) will measure land surface soil moisture content and whether the ground is frozen or thawed. Data is collected for the entire globe every two to three days.

SMAP’s lightweight mesh reflector rotates once every four seconds, gathering signals for the satellite’s onboard radar and radiometer instruments.

Soil moisture regulates plant growth and affects how heat is exchanged between the ground and the clouds in the atmosphere. The extremes of oversaturated ground and drought can be harmful to life on Earth. 

The water cycle describes the constant movement, driven by the energy of the sun, of water above, on and below the surface of the Earth. With the SMAP satellite’s data, researchers will gain insights into the state of water, and therefore life, around the world.

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